Valve-gear



(No Model.)

E. F. SPAULDING.

VALVE GEAR. No. 362,400. Patented May 3. L887.

Urn-TED STATES ATENT OFFICE.

ONE-THIRD TO JOHN K. HALLOOK, OF ERIE, PENNSYLVANIA VALVE-GEAR.

. SPECIFICATION forming part of To aZZ whom it mag/concern:

Be it known that I, ELIJAH F, SPAULDING, a citizen of the United States,residing at Oil City, in the county of Venango and State ofPennsylvania, have invented certain new and useful Improvements inValve-Gears for Steam- Engines; and I do hereby declare the following tobe a full, clear, and exact description of the invention, such as willenable others skilled in the art to which it appertains to make and usethe same.

This invention relates to valvegears for steam-engines; and it consistsin certain improvements in the construction thereof, as will behereinafter described, and pointed out in the claims.

My invention is illustrated in the-accompanying drawings, as follows:

Figure 1 is a top or plan view of my improved steam-engine valve-gear.Fig. 2 is a side elevation of-the same.- Fig. 3 is an end elevationtaken from the right of Figs. 1 and 2. Fig. 4 is an elevation view ofthe slide G unobstructed by other parts.

S is the engine-shaft. Vis the engine-valve. D is the valvestem. O isthe eccentric-rod. E is the main eccentric. E is the main-eccentricstrap. F is the auxiliary eccentric. F is the auxiliaryeccentric strap.F is a sleeve for connecting the auxiliary eccentric with any desirablegoverning device.

Other parts will be properly indicated by letters of reference in properplace in the following general description.

The main eccentric is fixed to the shaft, and

the auxiliary eccentricis loose upon the shaft,

and will be rolled thereon by the governing device, which is not shown,but which connects with the pins f on the sleeve F".

The main-eccentric strap E has an arm, E extending above the shaft, bywhich it engages with the eccentric-rod, and a second arm E whichextends below the shaft and carries a pin, e, with friction-roller e,which lies in a groove, 9, in the face of a slide, G, guided in guidesG, which will ordinarily be fixed to the bed of the engine. It willtherefore be seen that the eccentric-strap E, with its arms E and E ate,its weight at c, where it connects with the becomes a lever, having itsfulcrum Letters Patent No. 362,400, dated May 3, 1887. Application filedFebruary 17, 1887. Serial No. 227,927.

(No model.)

eccentric-rod O, and its power at E, which is the'main eccentric. Theshifting or auxiliary eccentric strap F has an extension or arm, E,which extends below the shaft and engages a pin, fixed in the slide G.It will therefore be noted that the eccentric F as it rotates willreciprocate the slide G.

In the face of the slide G is a groove, which deviates from a straightcourse. It is straight at top and bottom, but angles near its middlepart. As the pin e of the eccentricstrap lever E E E is set in the slot9, and as this slot is angular in its course, and as the slidecontaining said both up and down, the said strap-lever will be moved.Whenever so moved, the fulcrum of the strap-lever will be on theeccentric, the power at the pin 6, and the weight at the point 0. Itwill be seen, also, that any such movement will move the valveindependent of the eccentric. It will also be seen that this independentmovement will occur twice in each revolution of the eccentric E. It willalso be seen that the points where it will occur may be varied byrolling the eccentric F on the shaft, and thus changing the lead of theslide G, which operation will be performed by the governing device.

As shown in the drawings, the valve has been brought by the revolvingshaft and eccentric E in the direction of the full-line arrow to a pointjust ready to open the steamport and admit steam to the cylinder, andthe main eccentric E not havingreached its deadcenter, the movement ofthe valve will be continued and the port opened if no other influence isbrought to bear on the valve; but it will be observedthat the positionof the cutoff eccentric F and the direction of its movement is to movethe slide G down, and has moved it to a point where the offset in thegroove 9 is in contact with the pin 6 on the arm E of the strap-lever EE E and that any further movement-will carry the pin e through theoffset in the groove and this will move the strap-lever E E on theeccentric as a fulcrum, and draw the valve back and prevent it opening.Now, if the eccentric .F were .slightly shifted in the direction of theslot is reciprocated, it will I be seen that at each'movement of theslide,

dotted arrow, the pin 0 on the arm E would be in the straight part ofthe groove, and the port would be opened by the valve.

The amount that the valve opens the port and the time of closing dependon the relative positions of the two eccentrics, and this is to beregulated by the governing device.

I do not show a governing device, because almost any of the well-knowndevices may be used, and its operation forms no part of this invention.The main eccentric being keyed to the shaft, the ports will be openedand closed to the exhaust, and to admit steam to the cylinder at thesame point in the stroke of the piston, as the pin a 011 the arm of themain-eecentric strap will at such times always be in the straight partof the groove 9 in the slide G. The same movement of the valve as isproduced by my gear has been effected by other gears-as, for example,see Patent No. 12,729, to Scheuck, April 17, 1855, and No. 287,879, toSkinner, November 6, 1883; but in each of those cases cams on the shaftand levers pivoted off of the shaft, and provided with followers forengaging said cams, are used. Such devices cannot be employed on enginesrunning at high speed without much noise and inaccuracies.

My device, it will. be seen, is much simpler in construction, and isentirely positive in its action, and may be run at high speed withoutrattling, and it is entirely different in its construction.

\Vhat I claim as new is- 1. In the valve-gear of a StGftllLCllglllO, thecombination, substantially as shown, of two eccentrics on theengine-shaft, one fixed and the other shiftable, a strap around theshiftable eccentric, with an arm extending therefrom carrying areciprocating cam, a strap around the fixed eccentric having an armextending therefrom, which engages with the said reciprocating cam in amanner substantially as shown, whereby the reciprocations of said camwill oscillate the said strap on the fixed eccentric, and gearing foroperating the valve of the engine from said strap on the fixedeccentric. Y

2. In the valvegear of a steam-engine, the combination, substantially asset forth, of two eccentrics on the shaft, one fixed and the othershiftable, a strap on the shiftable eccentric, which connects with andreeiprocates a sliding cam, and a strap on the fixed eccentric which hasone arm to which the valve-rod is connected and another arm whichengages said sliding cam in a mannersubstantially as shown, whereby thesaid cam will rock the said strap on the fixed eccentric as it isreciprocatcd by the shiftable eccentric.

3. In a steam-engine valve-gear, the combination, substantially as setforth, of the eccentrics E and F on the shaft of the engine, of which Eis fixed and F is shiftable, and is provided with means for connectingit with a governing device, the eccentric-strap F on the eccentric F,having an arm, F, connecting with the pin g on the cam-slide G, and theeccentric-strap E on the eccentric E, having arms E and E, of which thearm E connects with the valve-rod, and the arm E engages with the cam inthe cam-slide G.

In testimony whereof I affix my signature in presence of two witnesses.

ELIJAH F. SPAULDING.

Witnesses:

EDWIN SQUinn, HARLEY W.- FISHER.

